Multi-roll stands

ABSTRACT

A multi-roll stand provided with two positively driven backing rolls and two working rolls frictionally driven by the backing rolls, in which the working rolls are displaced, for their horizontal support, with their axes out of the vertical plane containing the axes of the backing rolls, and intermediate rolls and supporting rollers journalled in supporting bridges provide further horizontal support for the working rolls. Means are provided for adjusting the lateral distance of the individual supporting rollers from the plane containing the axes of the backing rolls.

' 1970 K. LEIFELD ETAL v 3,546,914

MULT I -ROLL STANDS Filed June 20, 1967 5 Sheets-Sheet 1 Dec. 15, 1970 LElFELD ETAL 3,546,914

MULTI-ROLL STANDS Filed June 20, 1967 S'Sheets-Sheet 2 127 sous 3338 2 Dec. 15, 1970 K. LEIFELD ETAL 'MULTI-ROLL STANDS 5 Sheets-Sheet 3 Filed June 20, 1967 REIT? S I Dec. 1i; 1:71 I i 57 56 W 5: a 77% Dec. 15, 1970 LElFELD ETAL v 3,546,914

MULTI-ROLL STANDS Filed June 20, 1967 5 Sheets-Sheet 5 3,546,914 MULTI-ROLL STANDS Klaus Leifeld, Kaarst, Josef Wochnik, Osterath, and Erich Stoy, Dusseldorf, Germany, assignors to Schloemann Aktiengesellschaft, Dusseldorf, Germany, a German company Filed June 20, 1967, Ser. No. 647,451 Claims priority, appiication Germany, June 28, 1966, Sch 39,179 Int. Cl. 1321b 13/14 US. Cl. 72-242 2 Claims ABSTRACT OF THE DISCLOSURE A multi-roll stand with two positively driven backing rolls and two working rolls frictionally driven by the backing rolls, the working rolls being displaced, for their horizontal supporting, with their axes out of the vertical plane containing the axes of the backing rolls, further horizontal support for the working rolls being afforded by intermediate rolls and by supporting rollers journalled in supporting bridges, and means being provided for adjusting the lateral distance of the individual supporting rollers from the plane containing the axes of the backing rolls.

BACKGROUND OF THE INVENTION This invention relates to a multi-roll stand with two positively driven backing rolls, and two working rolls frictionally driven by the backing rolls. For taking up the horizontal forces acting upon the working rolls and conditioned by the frictional drive in such cases it is known to shift the working rolls from the vertical axial plane of the backing rolls, and to support them on their bodies in the direction of the shift by way of intermediate rolls against supporting rollers journalled on rigid supporting bridges. By a pressure-applying device at their bearing journals the working rolls are fixed against displacement in the opposite direction.

For the purpose of obtaining rolled stock of uniform cross-section, use is made of working rolls the body diameter of which increases by a small amount towards the middle. This camber must be adapted to the bending and flattening of the rolls under the particular rolling conditions, so that a plurality of pairs of working rolls must always be kept available. For the body correction during the rolling operation it is also known to cool the bodies of the rolls more strongly laterally than in the middle, or conversely. This method however is not sufiiciently precise, and is associated with some delay.

SUMMARY OF THE INVENTION The object of the present invention is to provide a device for roll-body correction, by means of which the roll profile can be accurately and quickly altered during the rolling operation. According to the invention, therefore, an adjusting device is provided for the variable changing, in the direction of a deflection, of the lateral distance of the individual supporting rollers from the common axial plane of the backing rolls. In the loading, effected with rolling mills of this construction, of the working rolls by lateral forces, the working rolls arranged between the positively driven backing rolls are pressed towards the supporting rollers, and are thus positively or negatively deflected in a horizontal direction. By this means, the height of the roll gap is varied symmetrically about the center of the path of rolling contact, over the breadth of the roll, so that as the rolled stock passes through, the most advantageous distribunied States atent tion of pressure for obtaining a rectangular cross-section of rolled stock is attained.

In a further development of the invention, a change of position of the supporting rollers is obtained by providing the supporting bridges with a deflection device for changing the form of their supporting surfaces, which upon actuation of the device, are displaced from their position of parallelism to the common axial plane of the backing rolls. The supporting bridges bear on housings provided with shackles in which a tension rod, with its screw-threaded ends, is accommodated in each case in a sleeve, the tension rod being connected, by way of a lever fastened thereto, with the piston-rod or connecting-rod of an adjusting cylinder. For influencing the form of its bending line, the supporting bridge may be provided with notches in the region of its supporting surface.

A particularly simple embodiment of the invention described is suitable for roll stands up to a breadth limited by the magnitude of the forces occurring. In the case, more particularly, of very wide rolling mills, it is advantageous, according to a further feature of the invention, to provide between the bearings of each supporting roller, or, between the bearings of groups of supporting rollers and the supporting bridges, wedges which are connected with adjusting elements, and which jointly form, according to the wedge angle and the position of the wedges relatively to one another in each case, a bearing contact extending positively or negatively according to a symmetrical arc, for the bearings of the supporting rollers. In a known roll stand, wedge-pieces are already arranged between the bearings of the supporting rollers and the supporting bridges. These, however, serve the purpose of an axially parallel adjusting of the supporting rollers during the stoppage, and not of a change in the lateral distance in the direction of a deflection, for the correction of camber during the rolling operation.

According to a further feature of the invention, wedges differing in the wedge angle are so arranged that those with the greatest angle bear in the middle of the supporting bridge, and with these are associated on both sides, wedges of a progressively diminishing angle, with the wedges being connected with piston-rods or, which are supported upon an eccentric shaft rockable by hydraulic means by way of a lever. The actuation of the shifting cylinder thus yields, symmetrically about the center of the rolling path, the adjusting travels requisite for the desired deflection of the working rolls.

Two constructional examples of the invention are illustrated in the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in horizontal section through a roll stand in the plane of the bending device for the supporting bridge, partly in the plane AB and partly in the plane C-D of FIG. 2;

FIG. 2 is a view in vertical section, in two related planes AB and C-D of FIG. 1, through the roll stand;

FIG. 2a shows the roll stand in end elevation, looking in the direction of the arrow 2a in FIG. 2;

FIG. 3 is a view in vertical section through a roll stand with adjusting wedges; and

FIG. 4 is a view looking at FIG. 3 in the direction towards a row of wedges bearing on the supporting bridge with their adjusting means.

DETAILED DESCRIPTION OF THE INVENTION Two working rolls 1, 1' of a multi-roll stand are supported vertically against backing and driving rolls 3, 3' journalled in chocks 2, 2, with the axes of the working rolls being displaced from the vertical plane of the axes of the backing rolls. In the direction of this displacement, the working rolls are supported by intermediate rolls 4, 4', 5, 5' on supporting rollers 6, 6, which are journalled in combs 7, 7 bearing horizontally on supporting bridges 10, 10 connecting the housings 8, 9. Perpendicularly, the combs 7, 7' have a bearing contact on beams 11, 11' which extend parallel to the rolls and are anchored to the chocks 2, 2. Between the upper and lower combs 7 and 7 are arranged pressure-fluid cylinder-piston units 12, which hold the same against their contact surfaces.

The supporting bridges 10, 10" are provided at their ends with shackles 13, which bear laterally on the housings 8 and 9, and are connected with housings by wedges or keys 8' and 9'. In the free ends of the shackles are accommodated sleeves 14, having screw-threaded apertures into which are screwed the ends, provided with right-handed and left-handed threads, of a tension rod 15. Upon the tension rod a lever 16 is secured by serrated arrangement. The lever is in each case connected, by way of a rod 17, with piston 18 of an adjusting cylinder 19, which is pivotally mounted in a hood 20 anchored to the supporting bridge 10. As FIGS. 1 and 2a show, the hoods 20 do not extend over the entire breadth of the supporting bridge 10, but are provided only in the region of the cylinders 19. The hoods 20 are therefore only slightly influenced by the bending of the supporting bridges. When the cylinder 19 is supplied with pressure fluid, the piston 18, by way of the lever 16, adjusts the tension rod 15 by imparting rotation thereto, whereby the latter draws the shackles 13 of the supporting bridges 10, 10" towards one another, and thus deflects the supporting bridges 10, 10. This deflection is transmitted, by way of the supporting rollers 6, 6 and the intermediate rolls 4, 4, 5, 5 to the working rolls 1, 1. For the purpose of obtaining as uniform a deflection as possible, the supporting bridges 10, 10" are provided, at the roller side, with notches 21. By the notches 21 the cross section of the supporting bridges 10' and 10' at the positions in question is reduced. By such notches the bending characteristic of the supporting bridge can be fixed to correspond to the requirements.

The intermediate rolls 4, 4' are journalled in rockable arms 22, 22, in which also the intermediate rolls 5, 5 are journalled in a slide block 23 slidable therein. In the arms 22, 22' are arranged compressed-air cylinders 24, in which, at the rear side, supporting forks 25 constituting pistons which serve for centering the bearings of the working rolls to the axial plane of the intermediate rolls 4, 4', 5, 5' are displaceable. The upper arms 22 are secured by tension springs 26 to the upper chocks 2, so that even when the supporting rollers 6 are being dismantled, the intermediate rolls 4 bear against the upper backing roll.

For securing the bearings of the working rolls oppositely to the intermediate rolls 4', 4', 5, 5, claws 27, 27 are provided, with each of them being slidable in a vertical guide 28 of a slide-piece defined by a head 29 and a guiding member 30. The slide-piece is displaceable horizontally transversely to the rolls, and its guiding member 30 is guided on the chock 2 and in a yokelike guiding body 31 secured to the chock 2. A piston 32 of a cylinder 33 provided in the guiding body 31 is directed towards the rear side of the head 29. In the piston 32 is arranged a cylinder 34 having a piston 35 which exerts a horizontal force upon a transmission lever 36 fulcrumed in the head 29. This horizontal force directed as a vertical force against the backing rolls, 3, 3' is transmitted to the claws 27, 27', and thus holds the working rolls 1 against the backing rolls 3, 3'.

. In the guiding member 30- of the slide-piece is provided a cylinder 3-7 having a piston rod 38 anchored to the chock 2. Upon energization, the slide-piece, together with the claw, is drawn back, whereby the dismantling of the working rolls 1, 1 is rendered possible. Between the upper and lower arms 22, 22' are arranged pressure-fluid cylinder-piston units 39, which support the upper arms 22, and prevent the intermediate rolls 4, 5 from falling down when the working rolls 1, 1' are dismantled.

In the multi-roll stand illustrated in FIGS. 3 and 4, two working rolls 46' are supported perpendicularly against backing and driving rolls 42 journalled in chocks 41, with the axes of the working rolls being displaced from the vertical backing-roll plane. In the direction of this displacement, the Working rolls are supported, by way of intermediate rolls 43, on supporting rollers 44 journalled in bearing plates 45, which are connected by a bolt 46. The bearing plates 45 are held by fluidpressure cylinder-piston units 47 against supporting beams 48, connected with the chocks 41. For taking up the horizontal supporting forces, supporting bridges 49 connect the housings and wedges 50 or 52 secured to the supporting bridge are arranged between the supporting bridges and bearing plates 45. Also, movable adjusting wedges 51 or 53 are provided.

The position of two outer adjusting wedges 53 is variable by means of intervening layers 54 and can be fixed by means of screws 55, in order to straighten the supporting rollers 44 with their axis parallel during stoppage.

The inner adjusting wedges 51 are connected with piston-rods or connecting-rods 56, which are accommodated upon an eccentric shaft 57, which is journalled upon the supporting bridge 49. Upon the eccentric shaft are anchored levers 58, which are connected with hydraulic cylinders 59 having piston-rods 60 thereof pivoted to the supporting bridge 49.

Of the adjusting wedges 51 actuated by the eccentric shaft 57, the two inner ones have a greater inclination than the outer ones. The ditfering inclinations of the wedges have the result that when pressure fluid is supplied to the cylinders 59, their contact surfaces designed for the bearing plates 45 extend in an arc.

Upon loading the working rolls 40', these rolls are pressed by the lateral forces, with the intermediate rolls 43, against the supporting rollers 44, and are thus positively or negatively deflected in a lateral direction, whereby the height of the roll gap is varied over the body breadth. In this manner also the most advantageous distribution of pressure can be obtained for the attainment of a rectangular rolled-stock cross-section.

We claim:

1. A Inulti-roll stand comprising: roll housings, deflectable supporting bridges connecting the roll housings, two positively driven backing rolls, two working rolls frictionally driven by the backing rolls, the axes of the working rolls being displaced from the vertical plane containing the axes of the backing rolls for the horizontal supporting of the working rolls, supporting rollers journalled in the deflectable supporting bridges, intermediate rolls interposed between the working rolls and the supporting rollers to aflord horizontal support to the working rolls, means for adjusting the lateral distance of the individual supporting rollers from the plane containing the axes of the backing rolls, shackles by which the supporting bridges bear on the roll housings, tension rods accommodated in the shackles, internally screw-threaded sleeves provided in the shackles, tension rods having external right and left-hand threads at the ends thereof accommodated in the said sleeves, adjusting cylinders, pistons slidable in the adjusting cylinders, and levers secured upon the tension rods connecting the tension rods with the pistons operative upon pressure fluid being supplied to the cylinders to rotate the tension rods and thereby draw the shackles together thus deflecting the supporting bridges and transmitting the deflection via the supporting rolls and intermediate rolls to the working rolls.

2. The multi-roll stand as claimed in claim 1, in which the supporting bridges are provided with notches along 5 6 the side in which the supporting rollers are journalled, 3,003,373 10/1961 Volkhausen 72-243 with said notches influencing the form of their bend- 3,373,590 3/1968 Knappe 72- 243 ing lines.

References Cited CHARLES W. LANHAM, Primary Examiner UNITED STATES ENTS 5 B. I. MUSTAIKIS, Assistant Examiner 1,905,129 4/1933 Biggert et a1. 72-237 US, Cl, X.R,

2,927,489 3/ 1960 Teutsch 72-243 72243 

